title: COX-(2) overexpression in sinonasal inverted papilloma.
abstract: BACKGROUND
  Inverted papilloma (IP) is a benign, but locally aggressive neoplasm of the nasal cavity and paranasal sinuses. The mainstay of treatment of IP is surgical resection, but high rates of tumor recurrence have been reported. Cyclo-oxygenase-2 (COX-2) has been found to be overexpressed in many tumors and has been used successfully as a therapeutic target. The goal of this study is to highlight COX-2 expression in IP.
  
  
  METHODS
  Immunohistochemistry for COX-2 was performed on IP samples obtained during surgical resection between January 2012 and June 2013. The intensity of staining was evaluated by 2 head and neck pathologists blinded to the clinical features and outcomes. A positive stain was defined as having 10% or more of tumor cells exhibiting immunoreactivity.
  
  
  RESULTS
  The study includes 13 tumor samples from 7 females and 6 males. Mean age was 54.5 (range, 18-81) years. Tumor locations included: nasal septum (1), ethmoid (3), sphenoid (4), and maxillary (5) sinuses. No tumors demonstrated malignancy or dysplasia. Five (38%) of the 13 IP samples stained strongly positive for COX-2, and 3 of 13 (23%) stained weakly positive. There were no clinical differences in patients that stained strongly or weakly for COX-2.
  
  
  CONCLUSIONS
  COX-2 overexpression was identified in 62% of cases of IP in this study, and strongly positive in 38% of cases. Larger studies are necessary to identify the true incidence of COX-2 expression for this tumor. Pharmaceuticals targeting COX-2 may eventually provide an additional therapeutic option for select cases of recurrent or unresectable IP.
authors.affiliation: Department of Head and Neck Surgery, University of California, Los Angeles, Los Angeles, CA.
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Suh
authors.forename: Fernando
authors.initials: F
authors.lastname: Palma-Diaz
authors.forename: Sunita
authors.initials: S
authors.lastname: Bhuta
authors.forename: Marilene B
authors.initials: MB
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009300:Nasal Septum / Q000378:metabolism*; D009669:Nose Neoplasms / Q000378:metabolism; D018308:Papilloma, Inverted / Q000378:metabolism*; D010255:Paranasal Sinus Neoplasms / Q000378:metabolism*
chemical_list: D051546:Cyclooxygenase 2
keywords: COX-2; cyclo-oxygenase; endoscopic sinus surgery; inverted papilloma; sinus tumor